1. Field of the Invention
The present invention relates to a semiconductor yaw rate sensor of a transistor type used, for example, in body control system or navigation system of a vehicle, and to a method of producing the same.
2. Related Arts
A vibration gyroscope is disclosed in United Kingdom Patent Application Publication No. GB 2 223 309 A and is described as a yaw rate sensor that detects yaw rate and the like that act upon a body of a vehicle, for example. Such a vibration gyroscope has a vibrator wherein a piezoelectric element is glued to a specified surface of a square rod made of metal, and is structured such that this is supported by means of a fine rod. An angular speed sensor disclosed in Japanese Patent Application Laid-open No. 4-142420 has a piezoelectric element glued to a tuning fork made of metal. In either case, these devices used to detect the acceleration of yaw rate and the like subject the main unit to vibration with a piezoelectric element, and attempt to detect, by means of changes in voltage detected by the piezoelectric element, distortion generated by a Corioli's force generated by means of the yaw rate which is the subject of measurement.
Performance such as detection sensitivity in a sensor mechanism structured in this manner comes to be influenced by the method of support and machining precision of the vibrator. Consequently, in order to produce a high-performance sensor mechanism, there exist the problems of a high degree of difficulty in the machining and assembly thereof, and of necessarily high cost corresponding to the requisite time and difficulty of machining and assembly. Additionally, with respect to achieving smaller size of the sensor mechanism as well, difficulty is encountered due to limitations in machining and assembly.